import os
from importlib.util import source_hash

print("hello world")

username = "zhangsan"

print(f"hello {username}")

try:
    print("hello world")
    username = "zhangsan"
    print(f"hello {username}")
except Exception as e:
    source_hash(e)

print(os.listdir(os.getcwd()))


nums = (100, 200, 300)


nums_array = [100,200,300]

nums[2] = 50
nums_array[2] = 500

print(f'{nums}, {nums_array}')